Flatout Suspension 17-24 Audi A4 B9 [GR40] GR4-AUDIA4B9

DISCLAIMER: This is a made to order item. The lead time for this product is 4-8 weeks.

The Flatout GR40 Coilovers for the 2017-2024 Audi A4 B9 are engineered for serious rally and motorsport drivers who demand precision, strength, and consistency under extreme conditions.

Designed as a 0–2 inch adjustable rally competition suspension system, the GR40 allows you to increase ride height and fine-tune chassis setup for tarmac, gravel, and rallycross applications. Whether you're building a dedicated rally car or a dual-purpose performance machine, this system delivers durability, control, and confidence.

The GR40 features inverted front shocks for maximum structural strength and reduced flex during high-impact driving. Select applications include external reservoir rear shocks for increased oil capacity, improved cooling, and fade resistance during extended competition use.

Flatout’s proprietary rally valving combined with bypass piston technology provides exceptional compliance at low speeds while maintaining outstanding high-speed control. The result is a suspension system that absorbs rough terrain comfortably yet remains composed and precise when pushed hard.

Soft rate LPS 2.5 ID linear springs deliver a balanced ride that transitions smoothly from transit stages to competitive driving. OEM-style top mounts preserve quiet operation and minimize NVH, making this system suitable for both competition and street-driven rally builds.

Electroplated shock bodies provide 7–10 years of corrosion resistance, while the fully rebuildable design ensures long-term serviceability. With 1-way rebound adjustment offering 20 points of tuning, drivers can dial in suspension behavior to match terrain and driving style.

Backed by a 3-year warranty, the Flatout GR40 is built for durability, performance, and long-term motorsport use.

FITMENT

Vehicle: Audi A4 B9

Years: 2017-2024

Chassis: B9

Application: Compatible with models equipped with factory strut suspension

Designed specifically for the 2017-2024 Audi A4 B9 platform.

Key Features

0–2" adjustable ride height increase
Inverted front shocks for maximum strength
External reservoir rear shocks on select applications
Proprietary rally valving with bypass pistons
Soft rate LPS 2.5 ID linear springs
OEM-style top mounts for reduced NVH
Electroplated shock bodies with long-term corrosion resistance
Fully rebuildable coilover design
1-way rebound adjustable with 20 tuning points
3-year manufacturer warranty

Why Choose the Flatout GR40

Built for rally, rallycross, and motorsport competition
Precision handling across gravel, tarmac, and mixed surfaces
Competition-ready durability with daily-drive refinement
Serviceable and customizable for long-term use
Proven in real-world rallycross and grassroots competition